Those aren't clear at all. They're clear to you because you don't see the weasel wording.
"Apple has never found [...]"
So what about third parties/reports/partners/contractors? Have they found anything and is Apple aware of those findings? Not disclosed here.
Are the QC processes in place sufficient to lead us to believe that Apple would/should have found this issue? etc. If not, who cares if they haven't found it.
Before you complain about the semantics, Apple specifically uses the phrasing "We are not aware of any" in respect of investigations, yet they don't use that all-encompassing language in reference to attacks.
"malicious chips, “hardware manipulations” or vulnerabilities purposely planted in any server"
What is a malicious chip - could the inserted piece be classified as non-malicious or simply not a chip? What is a hardware manipulation - are they saying they've literally never found any deviation between spec and what they've received? Why place 'purposely planted' as a qualifying requirement there?
"If there were ever such an event as Bloomberg News has claimed, we would be forthcoming about it and we would work closely with law enforcement."
They don't indicate what was claimed. They reference a volume of correspondence with a variety of claims instead of the claims. We assume, contextually, that they're referring to the specific chip insertion, but that's not borne out by their statement.
"No one from Apple ever reached out to the FBI about anything like this, and we have never heard from the FBI about an investigation of this kind — much less tried to restrict it."
This is fully plausible and means nothing. They restrict their denial of contact with the FBI to outgoing, indicate they haven't received notice of an investigation of some kind, which doesn't mean there's no investigation - collaborating with the FBI specifically on this point wouldn't involve the FBI disclosing the full scope of the investigation to them.
None of these statements actually deal with the issues claimed. They look like they do, but they don't.
Want a real statement? "Upon being notified of the potential issue by Bloomberg this past year, we have analyzed all of the SuperMicro boards referenced to determine if any unauthorized chip insertion occurred and have found none of the alleged inserted chips or any evidence of associated suspicious network activity."